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Let A = [12-13], B = [4015], C = [201-2] and a = 4, b = –2. Show that: (a + b)B = aB + bB - Mathematics

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Question

Let A = `[(1, 2),(-1, 3)]`, B = `[(4, 0),(1, 5)]`, C = `[(2, 0),(1, -2)]` and a = 4, b = –2. Show that: (a + b)B = aB + bB

Sum
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Solution

We have,

A = `[(1, 2),(-1, 3)]`

B = `[(4, 0),(1, 5)]`

C = `[(2, 0),(1, -2)]`

And a = 4, b = –2

(a + b)B = `(4 - 2) [(4, 0),(1, 5)]`   .....[∵ Given a = 4, b = –2]

= `[(8, 0),(2, 10)]`

Also, aB + bB

= 4B – 2B

= `[(16, 0),(4, 20)] - [(8, 0),(2, 10)]`

= `[(8, 0),(2, 10)]`

= `(a + b)B

Hence proved.

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Chapter 3: Matrices - Exercise [Page 57]

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NCERT Exemplar Mathematics [English] Class 12
Chapter 3 Matrices
Exercise | Q 32.(c) | Page 57

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